Background
Identification of functional lymphatic vessels and localization of lymphatic vessels are important for lymphaticovenular anastomosis (LVA). Indocyanine green (ICG) lymphography is useful ...for localization of superficial lymphatic vessels where dermal backflow is not observed, but not for lymphatic vessels in deep layer or where dermal backflow is observed. Ultrasound has been applied in LVA and is considered useful for localization of lymphatic vessels with ICG lymphography cannot be visualized.
Methods
Fifty‐five secondary lower extremity lymphedema (LEL) patients who underwent LVA were classified into two groups, ultrasound‐detection‐of‐lymphatic group (US group, n = 29) and non‐ultrasound‐detection‐of‐lymphatic group (non‐US group, n = 26), and assessed. Sensitivity and specificity to detect lymphatic vessel were evaluated in US group. Intraoperative findings, required time for dissecting lymphatic vessels and veins, length of skin incision, and postoperative lymphedematous volume reduction were compared between the groups.
Results
Lymphatic vessels were detected in all incisions in both groups. LVA resulted in 232 anastomoses in US group and 210 anastomoses in non‐US group. Sensitivity and specificity of ultrasound for detection of lymphatic vessels were 88.2% and 92.7%, respectively. Diameter of lymphatic vessels found in US group was significantly larger than that in non‐US group (0.66 ± 0.18 vs 0.45 ± 0.20 mm; P = 0.042). Time required for dissecting lymphatic vessels and veins in US group was shorter than that in non‐US group (9.2 ± 1.7 vs 14.7 ± 2.4 min; P = 0.026). LEL index reduction was significantly greater in US group than that in non‐US group (26.7 ± 13.6 vs 7.8 ± 11.3; P = 0.031).
Conclusions
Ultrasound‐guided detection of lymphatic vessels for lymphedema was performed with high precision, and allows easier and more effective LVA surgery.
This study sought to characterize temporal trends, patient-specific factors, and geographic variation associated with amputation in patients with lower-extremity peripheral artery disease (LE PAD) ...during the study period.
Amputation represents the end-stage failure for those with LE PAD, and little is known about the rates and geographic variation in the use of LE amputation.
By using data from the Centers for Medicare & Medicaid Services (CMS) from January 1, 2000, to December 31, 2008, we examined national patterns of LE amputation among patients age 65 years or more with PAD. Multivariable logistic regression was used to adjust regional results for other patient demographic and clinical factors.
Among 2,730,742 older patients with identified PAD, the overall rate of LE amputation decreased from 7,258 per 100,000 patients with PAD to 5,790 per 100,000 (p < 0.001 for trend). Male sex, black race, diabetes mellitus, and renal disease were all independent predictors of LE amputation. The adjusted odds ratio of LE amputation per year between 2000 and 2008 was 0.95 (95% CI: 0.95-0.95, p < 0.001).
From 2000 to 2008, LE amputation rates decreased significantly among patients with PAD. However, there remains significant patient and geographic variation in amputation rates across the United States.
Background
Although diabetic and atherosclerotic vascular diseases have different pathophysiological mechanisms, the screening methods currently used for diabetic lower‐extremity vascular diseases ...are mainly based on the evaluation methods used for atherosclerotic vascular diseases. Thus, assessment of microvascular perfusion is of great importance in early detection of lower‐extremity ischemia in diabetes.
Purpose
This cross‐sectional study aimed to develop a quantitative model for evaluating lower‐extremity perfusion.
Methods
We recruited 57 participants (14 healthy participants and 43 diabetes patients, of which 16 had lower‐extremity arterial disease LEAD). All participants underwent technetium‐99 m sestamibi (99mTc‐MIBI) scintigraphy and ankle‐brachial index (ABI) examination. We derived two key perfusion kinetics indices named activity perfusion index (API) and basal perfusion index (BPI). This study was registered in ClinicalTrials.gov (URL: https://www.ClinicalTrials.gov, NCT02752100).
Results
The estimated limb perfusion values in our lower‐extremity perfusion assessment (LEPA) model showed excellent consistency with the actual measured data. Diabetes patients showed reduced lower‐extremity perfusion in comparison with the control group (BPI: 106.21 ± 11.99 vs. 141.56 ± 17.38, p < 0.05; API: 12.34 ± 3.27 vs. 14.56 ± 3.12, p < 0.05). Using our model, the reductions in lower‐extremity perfusion could be detected early in approximately 96.30% of diabetes patients. Patients with LEAD showed more severe reductions in lower‐extremity perfusion than diabetes patients without LEAD (BPI: 47.85 ± 20.30 vs. 106.21 ± 11.99, p < 0.05; API: 7.06 ± 1.70 vs. 12.34 ± 3.27, p < 0.05). Discriminant analysis using API and BPI could successfully screen all diabetes patients with LEAD with a sensitivity of 100% and specificity of 80.77%.
Conclusions
We established a LEPA model that could successfully assess lower‐extremity microvascular perfusion in diabetes patients. This model has important application value for the recognition of early‐stage LEAD in patients with diabetes.
Summary Background Lower extremity peripheral artery disease is the third leading cause of atherosclerotic cardiovascular morbidity, following coronary artery disease and stroke. This study provides ...the first comparison of the prevalence of peripheral artery disease between high-income countries (HIC) and low-income or middle-income countries (LMIC), establishes the primary risk factors for peripheral artery disease in these settings, and estimates the number of people living with peripheral artery disease regionally and globally. Methods We did a systematic review of the literature on the prevalence of peripheral artery disease in which we searched for community-based studies since 1997 that defined peripheral artery disease as an ankle brachial index (ABI) lower than or equal to 0·90. We used epidemiological modelling to define age-specific and sex-specific prevalence rates in HIC and in LMIC and combined them with UN population numbers for 2000 and 2010 to estimate the global prevalence of peripheral artery disease. Within a subset of studies, we did meta-analyses of odds ratios (ORs) associated with 15 putative risk factors for peripheral artery disease to estimate their effect size in HIC and LMIC. We then used the risk factors to predict peripheral artery disease numbers in eight WHO regions (three HIC and five LMIC). Findings 34 studies satisfied the inclusion criteria, 22 from HIC and 12 from LMIC, including 112 027 participants, of which 9347 had peripheral artery disease. Sex-specific prevalence rates increased with age and were broadly similar in HIC and LMIC and in men and women. The prevalence in HIC at age 45–49 years was 5·28% (95% CI 3·38–8·17%) in women and 5·41% (3·41–8·49%) in men, and at age 85–89 years, it was 18·38% (11·16–28·76%) in women and 18·83% (12·03–28·25%) in men. Prevalence in men was lower in LMIC than in HIC (2·89% 2·04–4·07% at 45–49 years and 14·94% 9·58–22·56% at 85–89 years). In LMIC, rates were higher in women than in men, especially at younger ages (6·31% 4·86–8·15% of women aged 45–49 years). Smoking was an important risk factor in both HIC and LMIC, with meta-OR for current smoking of 2·72 (95% CI 2·39–3·09) in HIC and 1·42 (1·25–1·62) in LMIC, followed by diabetes (1·88 1·66–2·14 vs 1·47 1·29–1·68), hypertension (1·55 1·42–1·71 vs 1·36 1·24–1·50), and hypercholesterolaemia (1·19 1·07–1·33 vs 1·14 1·03–1·25). Globally, 202 million people were living with peripheral artery disease in 2010, 69·7% of them in LMIC, including 54·8 million in southeast Asia and 45·9 million in the western Pacific Region. During the preceding decade the number of individuals with peripheral artery disease increased by 28·7% in LMIC and 13·1% in HIC. Interpretation In the 21st century, peripheral artery disease has become a global problem. Governments, non-governmental organisations, and the private sector in LMIC need to address the social and economic consequences, and assess the best strategies for optimum treatment and prevention of this disease. Funding Peripheral Arterial Disease Research Coalition (Europe).
Aim
To analyse large‐scale cardiovascular outcome trials of sodium‐glucose co‐transporter‐2 (SGLT‐2) inhibitors to evaluate whether there are safety concerns with respect to major adverse limb events ...overall or among various high‐risk subgroups of patients.
Methods
We performed a quantitative meta‐analysis of randomized, placebo‐controlled, cardiovascular outcome trials of SGLT‐2 inhibitors in patients with type 2 diabetes. We searched the PubMed, Embase and Cochrane databases for trials published up until 30 June 2020. The efficacy outcomes analysed included amputations and were stratified by several subgroup variables, including age, duration of diabetes, glucose control, renal function, established peripheral artery disease and diabetes microvascular complications. This review was registered before completing the analysis.
Results
Among 383 records identified, six studies assessing the following three SGLT‐2 inhibitors met our inclusion criteria: empagliflozin (EMPA‐REG OUTCOME study), canagliflozin (CANVAS Program and CREDENCE study), dapagliflozin (DECLARE‐TIMI 58 and DAPA‐HF trials) and ertugliflozin (VERTIS CV study). Of a total of 51 713 participants, 858 required amputation operations. The event rates of amputation were 2.0% (535/26 778) and 1.3% (323/24 927) in the SGLT‐2 inhibitor and control groups, respectively. The random effects model revealed that SGLT‐2 inhibitors were not significantly associated with an increased risk of amputation with substantial heterogeneity (pooled risk ratio, 1.24; 95% confidence interval, 0.96 to 1.60; I2 = 67.5%). This neutral effect of SGLT‐2 inhibitors was also consistent across different levels of subgroups, including subgroups with or without established peripheral artery disease (PAD).
Conclusions
SGLT‐2 inhibitors are not associated with increased risks of amputation operations even among various high‐risk subgroups, including patients with PAD. The amputation events primarily arise from critical limb ischaemia and infection instead of acute limb ischaemia. A multi‐centre study focused on major adverse limb events with a longer follow‐up is needed to confirm these results and provide guidelines for clinical practice.
Exposure to acute prolonged sitting can result in vascular dysfunction, particularly within the legs. This vascular dysfunction, assessed using flow-mediated dilation (FMD), is likely the consequence ...of decreased blood flow-induced shear stress. With mixed success, several sitting interruption strategies have been trialled to preserve vascular function.
The objectives of this meta-analysis were to (1) assess the effects of acute prolonged sitting exposure on vascular function in the upper- and lower-limb arteries, and (2) evaluate the effectiveness of sitting interruption strategies in preserving vascular function. Sub-group analyses were conducted to determine whether artery location or interruption modality explain heterogeneity.
Electronic databases (PubMed, Web of Science, SPORTDiscus, and Google Scholar) were searched from inception to January 2020. Reference lists of eligible studies and relevant reviews were also checked.
Inclusion criteria for objective (1) were: (i) FMD% was assessed pre- and post-sitting; (ii) studies were either randomised-controlled, randomised-crossover, or quasi-experimental trials; (iii) the sitting period was ≥ 1 h; and (iv) participants were healthy non-smoking adults (≥ 18 years), and free of vascular-acting medication and disease at the time of testing. Additional inclusion criteria for objective (2) were: (i) the interruption strategy must have been during the sitting period; (ii) there was a control (uninterrupted sitting) group/arm; and (iii) the interruption strategy must have involved the participants actively moving their lower- or upper-limbs.
One thousand eight hundred and two articles were identified, of which 17 (22 trials, n = 269) met inclusion criteria for objective (1). Of those 17 articles, 6 studies (9 trials, n = 127) met the inclusion criteria for objective (2). Weighted mean differences (WMD), 95% confidence intervals (95% CI), and standardised mean difference (SMD) were calculated for all trials using random-effects meta-analysis modelling. SMD was used to determine the magnitude of effect, where < 0.2, 0.2, 0.5, and 0.8 was defined as trivial, small, moderate, and large respectively.
(1) Random-effects modelling showed uninterrupted bouts of prolonged sitting resulted in a significant decrease in FMD% (WMD = - 2.12%, 95% CI - 2.66 to - 1.59, SMD = 0.84). Subgroup analysis revealed reductions in lower- but not upper-limb FMD%. (2) Random-effects modelling showed that interrupting bouts of sitting resulted in a significantly higher FMD% compared to uninterrupted sitting (WMD = 1.91%, 95% CI 0.40 to 3.42, SMD = 0.57). Subgroup analyses failed to identify an optimum interruption strategy but revealed moderate non-significant effects for aerobic interventions (WMD = 2.17%, 95% CI - 0.34 to 4.67, SMD = 0.69) and simple resistance activities (WMD = 2.40%, 95% CI - 0.08 to 4.88, SMD = 0.55) and a trivial effect for standing interruptions (WMD = 0.24%, 95% CI - 0.90 to 1.38, SMD = 0.16).
Exposure to acute prolonged sitting leads to significant vascular dysfunction in arteries of the lower, but not upper, limbs. The limited available data indicate that vascular dysfunction can be prevented by regularly interrupting sitting, particularly with aerobic or simple resistance activities.
Purpose
Numerous daily tasks such as walking and rising from a chair involve bilateral lower limb movements. During such tasks, lower extremity function (LEF) may be compromised among older adults. ...LEF may be further impaired due to high degrees of between‐limb asymmetry. The present study investigated the prevalence of between‐limb asymmetry in muscle mass, strength, and power in a cohort of healthy older adults and examined the influence of between‐limb asymmetry on LEF.
Methods
Two hundred and eight healthy older adults (mean age 70.2 ± 3.9 years) were tested for LEF (400 m walking and 30‐seconds chair stand). Furthermore, maximal isometric and dynamic knee extensor strength, leg extensor power, and lower limb lean tissue mass (LTM) were obtained unilaterally.
Results
Mean between‐limb asymmetry in maximal muscle strength and power ranged between 10% and 13%, whereas LTM asymmetry was 3 ± 2.3%. Asymmetry in dynamic knee extensor strength was larger for women compared with men (15.0 ± 11.8% vs 11.1 ± 9.5%; P = .005) Leg strength and power were positively correlated with LEF (r2 = .43‐.46, P < .001). The weakest leg was not a stronger predictor of LEF than the strongest leg. Between‐limb asymmetry in LTM and isometric strength was negatively associated with LEF (LTM; r2 = .12, P = .005, isometric peak torque; r2 = 0.40, P = .03.) but dynamic strength and power were not.
Conclusion
The present study supports the notion that in order to improve or maintain LEF, healthy older adults should participate in training interventions that increase muscle strength and power, whereas the effects of reducing between‐limb asymmetry in these parameters might be of less importance.
Legged locomotion is the most common behavior of terrestrial animals and it is assumed to have become highly optimized during evolution. Quadrupeds, for instance, use distinct gaits that are optimal ...with regard to metabolic cost and have characteristic kinematic features and patterns of inter-leg coordination. In insects, the situation is not as clear. In general, insects are able to alter inter-leg coordination systematically with locomotion speed, producing a continuum of movement patterns. This notion, however, is based on the study of several insect species, which differ greatly in size and mass. Each of these species tends to walk at a rather narrow range of speeds. We have addressed these issues by examining four strains of Drosophila, which are similar in size and mass, but tend to walk at different speed ranges. Our data suggest that Drosophila controls its walking speed almost exclusively via step frequency. At high walking speeds, we invariably found tripod coordination patterns, the quality of which increased with speed as indicated by a simple measure of tripod coordination strength (TCS). At low speeds, we also observed tetrapod coordination and wave gait-like walking patterns. These findings not only suggest a systematic speed dependence of inter-leg movement patterns but also imply that inter-leg coordination is flexible. This was further supported by amputation experiments in which we examined walking behavior in animals after the removal of a hindleg. These animals show immediate adaptations in body posture, leg kinematics and inter-leg coordination, thereby maintaining their ability to walk.
Background and purpose - Hexapod ring fixators such as the Taylor Spatial Frame (TSF) have shown good outcomes. However, there have only been a few studies comparing the use of TSF with various ...etiologies of the deformity. We compared the use of TSF in congenital and acquired deformities in children.
Patients and methods - We reviewed 213 lower extremity reconstructive procedures with the TSF in 192 patients who were operated between October 2000 and October 2015. 128 procedures (67 proximal tibiae, 51 distal femora, and 10 distal tibiae) in 117 children (median age 14 (4-18) years; 59 girls) fulfilled the inclusion criteria. 89 procedures were done in children with congenital deformities (group C) and 39 were done in children with acquired deformities (group A). Outcome parameters were lengthening and alignment achieved, lengthening index, complications, and analysis of residual deformity in a subgroup of patients.
Results - Mean lengthening achieved was 3.9 (1.0-7.0) cm in group C and 3.7 (1.0-8.0) cm in group A (p = 0.5). Deformity parameters were corrected to satisfaction in all but 3 patients, who needed further surgery for complete deformity correction. However, minor residual deformity was common in one-third of the patients. The mean lengthening index was 2.2 (0.8-10) months/cm in group C and 2.0 (0.8-6) months/cm in group A (p = 0.7). Isolated analysis of all tibial and femoral lengthenings showed similar lengthening indices between groups. Complication rates and the need for secondary surgery were much greater in the group with congenital deformities.
Interpretation - The TSF is an excellent tool for the correction of complex deformities in children. There were similar lengthening indices in the 2 groups. However, congenital deformities showed a high rate of complications, and should therefore be addressed with care.
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